Cellulose-ether composition



Ill

Patented Aug. 11, 1925.

more!)v PATENT OFFICE.

HANS T. CLARKE, OF ROCHESTER, NEW YORK, ASSIGNOR TO EASTMAN KODAK COM-PAN'Y, OF ROCHESTER, NEW YORK, A CORPORATION OF NEW YORK.

CELLULOSE-ETHER COMPOSITION.

N o Drawing.

T 0 all whom it may concern:

' Be it known that I, HANS T. CLARKE, a subject of the King of GreatBritain, residing at Rochester, in the count of Monroe and State of NewYork, have invented certain new and useful Improvements inCellulose-Ether Compositions, of which the following is a full, clear,and exact specification.

This invention relates to a composition of matter in which celluloseother is combined or mixed with other substances, so that the resultingproduct can be advantageously used in the plastic and analogous arts,such or instance as sheet or film manufacture and varnish manufacture.

One object of the invention is to provide a composition which may bemade into ermanently transparent, strong and flexible sheets or films ofdesired thinness, which are substantially waterproof, are unafiected byordinary photographic fluids, and possess the desired roperties of asupport for light-sensitive photographic coatings. Another object of myinvention is to produce a composition capable of easy manipulation inthe plastic and film-making, or varnish making, or allied arts; but willnot injure or be injured by the substances with which it is associatedduring manufacture, storage or use. Still another object of my inventionis to provide a film having the hereinabove described properties. Otherobjects will hereinafter appear.

l have found that a composition having the desirable qualitieshereinabove enu merated can be obtained by mining or compoundingcellulose ether, say for example an alkyl ether of the type described inU. S. Patent No. 1,188,376, June 20, 1916, Leon Lilient'eld, withpentaerythritol tetracetate.

This mixing to a colloidized state is proton ably performed with the aidof a common solvent. l Vhile the details of one-way of carrying out myinvention will be given by way of example, it will be understood that myinvention is not restricted. thereto, ea".- cept as indicated in theappended claims.

.ln carrying out one embodiment oil my invention, 100 parts ofwater-insoluble ethyl cellulose are dissolved along with from 11 to 20parts of pentaerythritol tetracetate {say 15 parts) in from 300 to e00parts of a vole Application filed June 16, 19%. Serial No. 720,168.

tile common solvent. The latter may usefully comprise a mixture ofmethyl acetate and methyl alcohol, the weight of methyl acetate beingapproximately nine times the weight of the alcohol. This composition issuitable for spreading upon a film-forming surface in a coating, fromwhich the volatile solvent evaporates sufiiciently to leave atransparent flexible sheet, which is stripped 03 and otherwise treatedin the way well known in this art. The parts are by weight.

Where a more readily fiowable composition is desired, the amount ofvolatile solvent may be increased until the desired re sults areobtained. Benzol and ethyl or methyl alcohol may be added in thinning itout. Of course, other equivalent volatile solvent mixtures may besubstituted. Moreover, ingredients which impart characteristicproperties to the film may likewise be added, such as triphenylphosphate, tricresyl phosphate, camphor, monochlornaphthalene, etc. Theproportions of these substances, or mixtures of them, should not besufiicient to cause precipitation of the ether, or to cause white filmsor varnish coatings to be produced. The ingredients are of thecommercial type and suiliciently purified for the ends in view. Wherethe dopeis to be made into sheets or films for photographic purposes,the substances are chosen or puritied to have the proper relativefreedom from color.

Having thus described my invention, what ll claim as new and desire tosecure by Letters Patent is:

l. A composition in a colloidized state, comprising cellulose ether andpentacrythritol tetracetate.

2. A tlowable composition comprising cellulose ether, pentaerythritoltetracetate and a common liquid solvent.

3. A flowable composition comprising an allryl ether of cellulose,pentaerythritol tetracetate, and a common solvent comprisleast one of 5.As an article of manufacture, a sheet 7. As an article of manufacture, aflexible, comprising cellulose ether and pentaerythritransparent,deposited or flowed sheet, comto] tetracetate. prising water-insolubleethyl cellulose and 10 (3. As an article of manufacture, a depospentaerythritol tetracetate.

5 ited or flowed flexible sheet, comprising an Signed at Rochester, NewYork, this 10th alkyl ether of cellulose and pentaerythritol day ofJune, 1924. tetracetute. HANS T. CLARKE.

